Trapped-ion quantum simulator observes

A research team has observed string-breaking dynamics on a quantum simulator for the first time. The work, led by faculty at the Duke Quantum Center, was published in the journal Nature Physics on September 23, 2026.

String-breaking is a phenomenon where two connected fundamental particles are stretched apart. The energy that builds up in the connection can become so great that new particles pop into existence when it snaps. This process is analogous to the formation of particle-antiparticle pairs and requires extreme energy levels, like those found in particle colliders or the aftermath of the Big Bang.

Christopher Monroe, the Gilhuly Family Presidential Distinguished Professor of Electrical and Computer Engineering and Physics at Duke, led the research. "Quantum computer simulations provide the best platform to investigate complex questions like matter formation, short of having witnessed the Big Bang itself," Monroe said. The international collaboration included researchers from the University of Maryland, Oxford University, California Institute of Technology, Cornell University, and KU Leuven.

Simulating quark confinement

Quarks are fundamental building blocks of matter but are never found alone. They are confined inside particles like protons and neutrons. The team used a quantum simulator to recreate the dynamics of this confinement and the subsequent string-breaking process.

To perform the simulation, the researchers encoded a string-breaking model into a chain of 13 trapped ions. Precisely controlled laser beams tuned the interactions among the ions. These interactions controlled the system's energy in a way that mimicked the stretching and eventual snapping of a string connecting two charges.

By preparing the system in an out-of-equilibrium state and tracking its evolution, the team observed the emergence of effective charges and reconstructed the string dynamics. First author Arinjoy De, a former Ph.D. Student in Monroe's lab, said the work opens new pathways for investigating matter at its most fundamental level.

Verification and platform comparison

The team verified their quantum simulator results using a classical computer. For this scale of problem, both systems produced accurate and matching outcomes. However, as problem sizes grow in future experiments, only quantum computers will be capable of solving them.

This trapped-ion experiment is one of three recent simulations of the same phenomenon on different quantum computing platforms. Teams led by Google and QuEra Computing have recreated the string-breaking process on platforms built with superconducting circuits and neutral atoms, respectively.

"These are the three platforms leading the charge in quantum computing, so it's a nice benchmark and comparison for the quantum community," Monroe added. Each platform presents unique advantages and challenges for such simulations.

Toward probing the early universe

The results signal a development in quantum simulation for high-energy physics. The high controllability of quantum simulators allows them to recreate real-world processes occurring at subatomic scales in a lab environment.

Zohreh Davoudi, an associate professor of physics at the University of Maryland and part of the team, expressed excitement about the potential. As a physicist, it is incredibly exciting to investigate the conditions of the early universe in an atomic-level computing machine, Davoudi said.

The work is a step toward building quantum simulations complex enough to exceed the capabilities of the largest supercomputers. Such future simulations could allow researchers to explore fundamental questions, such as how matter evolved in the moments following the Big Bang. The team's findings were confirmed against classical computations, setting a benchmark for the trapped-ion platform's accuracy.